/Engine/Source/Runtime/CoreUObject/Public/Serialization/ArchiveReplaceOrClearExternalReferences.h
Identical toFArchiveReplaceObjectRef, but for references to private objects in other packages we clear the reference instead of preserving it (unless it makes it into the replacement map)
template<class T> class FArchiveReplaceOrClearExternalReferences : public [FArchiveReplaceObjectRef< T >](API\Runtime\CoreUObject\Serialization\FArchiveReplaceObjectRef)
UPackage*
DestPackage
Package that we are loading into, references to private objects in other packages will be cleared